Dogs wag(摇摆) their tails in different directions depending on whether they are excited and wanting to move forward or threatened and thinking of moving back, a study has found.
Researchers in Italy examined the tail wagging behaviour of 30 dogs, catching their responses to a range of stimuli(刺激物) with video cameras. To conduct the study they chose 15 male dogs and 15 female ones aged between one and six years. The dogs were all family pets whose owners had allowed them to take part in the experiment at Bari University. The dogs were placed in a large wooden box with an opening at the front to allow for them to view various stimuli. They were tested one at a time.
The researchers led by Professor Giorgio Vallortigara of the University of Trieste found that when the dogs were shown their owners—a positive experience—their tails wagged energetically to the right side. When they were shown an unfamiliar human they wagged to the right, but with somewhat less enthusiasm. The appearance of a cat again caused a right-hand side wag, although with less intensity again. The appearance of a large unfamiliar dog, similar to a German shepherd, changed the direction of tail wagging to the left. Researchers supposed the dog was thinking of moving back. When the dogs were not shown any stimuli they tended to wag their tails to the left, suggesting they preferred company. While the changes in the tail wagging were not easily noticed without the aid of video, it was thought that the findings could help people judge the mood (心情) of dogs. Computer and video systems, for example, could be used by professional dog trainers to determine the mood of dogs that they were required to approach.The video cameras were used to catch the dogs ’responses because .
| A．it was easier to catch the dogs’ response changes in the tail wagging |
| B．the dogs were put in the wooden boxes and tested one at a time. |
| C．they enabled the dogs’ owners to know about their dogs’ habit |
| D．the dogs wagged their tails in different directions when they were in different moods |
The underlined word“intensity” in the passage means .
| A．surprise | B．worry | C．excitement | D．interest |
When there are no stimuli, a dog will .
| A．wag to the left | B．wag to the right |
| C．not wag at all | D．wag to the left and then to the right |
The underlined word “they”in the last paragraph refers to .
| A．the dogs | B．the trainers | C．the systems | D．the researchers |
The purpose of doing the experiment is .
| A．to train dogs for their owners |
| B．to help people judge the mood of dogs |
| C．to help dogs find company |
| D．to help people choose their pet dogs |
Watercress is positively packed with healthy vitamins and minerals. The writings of both the Romans and the Ancient Greeks record the consumption of watercress by all classes. Hippocrates, “the father of medicine”, was so convinced that watercress was a great healer that he built his first hospital next to a stream so that he could grow a plentiful supply of the shiny green leaves for his patients. The Romans chewed watercress in large quantities, believing that it would cure baldness. They, too, looked with favor on watercress as a salad.
Watercress sandwiches were traditionally a breakfast item in nineteenth-century Europe. The most basic type of watercress sandwich has two pieces of white bread with a mixture of butter and watercress greens . A nickname(绰号)for the vegetable, in fact, was “poor man’s bread”, because watercress was often eaten on its own for breakfast by families that could not afford the bread to go with it.
Watercress is a member of the mustard(芥菜) family. It contains vitamins C(66mg per 100g), K and A, and is also a valuable source of minerals such as iron, potassium, copper and calcium. The mustard oils in its silky leaves and stems(茎)contain an ingredient known as PEITC. Recent research has proved that PEITC can prevent the growth of cancer cells and, in some cases, actually destroy them.
The best watercress has silky green leaves without any marks and has undamaged stems, The older the plant, the darker are its leaves and the thicker its stems. This means a higher concentration of oils and vitamins. Young watercress, on the other hand, may be harvested after only twenty-eight days growth and has a milder taste. It is best to eat watercress fresh and raw , to keep more of its valuable nutrients, but it can be lightly cooked and used as an alternative to spinach—another dark green vegetable—in various recipes. From soups to salads, watercress is now considered around the world as a natural and healthy super food.From paragraph 1, we can learn that________.
| A．watercress is usually grown in wet areas |
| B．the ancient Greeks only used watercress for medicine |
| C．watercress is the most ancient vegetable known to man |
| D．the Romans rubbed watercress on their heads to cure baldness |
The underlined word “it” in paragraph 2 refers to “_________”.
| A．butter | B．watercress | C．breakfast | D．bread |
Which of the following is TRUE about watercress?
A.It belongs to the same family as spinach.
B.It contains mustard oils only in leaves.
C.It can help guard against cancer.
D.It is rich in vitamins C and B.Compared with older watercress, young watercress .
| A．has lighter green leaves |
| B．contains more minerals |
| C．is better for medical use |
| D．is more suitable for eating raw |
What would be the best title for the text?
| A．The history of watercress | B．watrcress, a medicinal plant |
| C．Watercress, the amazing food | D．New findings about watercress |
Yawning sends out certain messages -either “Oh，this movie is so boring” or “I probably need to get some sleep”. But did you know that a yawn can also help your brain to cool down when it is overheated?
A new study, led by a research team at Princeton University, has indicated that yawning could be the brain’s natural way of regulating temperature. People yawn more often when the temperature outdoors is lower than their body temperature but are less likely to yawn when it is hotter outdoors, according to Sciencedaily. com.
The research team did an experiment on 160 people, 80 in summer and 80 in winter, to examine how often they yawned at different air temperatures. The study found that people yawned more often in winter than in summer. Scientists say that when the air temperature is lower outside the body, there is heat exchange between the overheated brain and the cool air. But when the air temperature is higher than or equal to the body, people are less likely to yawn because the hot air they breathe in will make the brain even hotter.
When people yawn, their jaw is also stretched，which increases blood flow and may also help cool the brain
The study showed that the amount someone yawned could be related to the amount of time they spent outside. The longer they spent outside in summer, the less they yawned. Nearly 40 percent of participants yawned within their first five minutes outside, but after that the percentage was reduced to less than 10 percent.
However, the result was the opposite in winter. The number of people who yawned increased when they spent more than five minutes outdoors. But the change was only slight compared to summertime.
According to Gallup, this is the first report to show that yawning frequencies change depending on season. This could help us to understand better the way our brains work. It may also help us understand the reason why frequent yawning can sometimes be a sign of brain disease.The purpose of the experiment is ______.
| A．to find the frequency of people’s yawning |
| B．to indicate brain can regulate temperature naturally |
| C．to prove people yawn in winter and in summer equally |
| D．to show the real reason why people yawn |
The information we get from Paragraphs 5 and 6 is that ______.
| A．longer outdoor summertime results in more yawns |
| B．yawning frequency increases with outdoor time |
| C．yawning frequency changes with outdoor time |
| D．longer outdoor wintertime leads to fewer yawns |
Acorrding to the text，people yawn more often ______.
| A．when the air temperature is equal to the body |
| B．when the hot air breathed in makes the brain hotter |
| C．when the air temperature is higher than the body |
| D．when the air temperature is lower outside the body |
What could be the best title for the text?
| A．Yawning Is A Sign of Brain Disease |
| B．Yawning Cools Your Brain |
| C．Yawning Benefits Your Body |
| D．Yawning Carries Some Information |
In the late 1970’s,many people in North America turned their attention to environmental problems ，and new steel — and — glass skyscrapers were widely criticized. Some ecologists (生态学家）pointed out that a number of tall buildings in a city often overburden public transportation.
Skyscrapers are also lavish consumers of electric power and water. In just one recent year, the addition of 17 million square feet of skyscraper office space in New York City itself has already raised the top daily demand for electricity by 120, 000 kw — enough to supply the entire city of Albany in New York area for a single day.
Glass—walled skyscrapers can also be especially wasteful. The heat loss ，or gain， through a wall of half 一 inch plate glass is more than ten times that through a typical ordinary wall filled with bricks or board. In order to decrease the pressure on heating and air — conditioning equipment, builders of skyscrapers have begun to use double—layered glass ，and reflective glasses coated with silver or gold mirror films that could reduce glare (强光）as well as heat gain. However, mirror — walled skyscrapers may raise the temperature of the surrounding air and affect neighboring buildings as well.
Skyscrapers put a severe pressure on a city's sanitation (卫生）facilities, too. If fully occupied, the towers just within the central area of New York would alone produce 2. 25 million gallons of waste water each year^—as much as the city size of Stanford， Connecticut, which has a population of more than 109，000.The underlined phrase“ lavish consumers ”in the 2nd paragraph probably means ____
| A．trash producers | B．great spenders | C．pressure makers | D．poor customers |
Glass walls of skyscrapers are specially mentioned in order to _____.
| A．show how skyscrapers manage to lessen their pressure |
| B．explain why skyscrapers can control its air conditions |
| C．describe further how wasteful skyscrapers could be |
| D．present the stability of skyscrapers in modern buildings |
From the last paragraph we can learn that _____.
| A．central New York skyscrapers are a large waste water producer |
| B．the central area of New York is as large as the city of Stanford |
| C．more than 109，000 people live in the skyscrapers in New York |
| D．New York produces 2. 25 million gallons of waste water each year |
When the writer talks about skyscrapers ，his tone sounds _____
| A．positive | B．doubtful | C．grateful | D．negative |
Thomas Jefferson, the third president of the United States, was a good and tireless writer, and he wrote The Declaration of Independence. There is much we can learn from him. Here are some of the things he said and wrote:
Go and see. Jefferson believed that a free man obtains knowledge from many sources besides books, and personal investigation is important as well.
Judge for yourself. Jefferson refused to accept other people’s opinions without careful thought. “Neither believe nor reject anything，” he wrote to his nephew.
Learn from everyone. Jefferson once visited the French nobleman, Lafayette, and said to him, “You must go into the people’s home as I have done ，look into their cooking pots and eat their bread. If you will only do this, you may find out why people are dissatisfied. ”
Do what you believe is right. In a free country, there will always be conflicting ideas， and this is a source of strength. It is not unquestioning agreement but conflict that keeps freedom alive. Though Jefferson was for many years the object of strong criticism, he never answered his critics. He expressed his philosophy, “There are two sides to every question. If you take one side with decision and act on it with effect, those who take the other side will of course resent(憎恶）your actions. ”
Trust the future and trust the young. Jefferson felt that the present should never be chained to customs which have lost their usefulness. “The earth belongs to the living generation. ” He didn’t fear new ideas, nor did he fear the future. “How much pain has been caused by evils which have never happened?” he remarked，“I expect the best, not the worst. ”The author mentioned Jefferson’s visit to Lafayette to show______.
| A．Jefferson was dissatisfied with Lafayette |
| B．Jefferson had a close relationship with his people |
| C．Jefferson was a great American president |
| D．Jefferson valued the importance of learning from others |
Jefferson was determined never to answer his critics because______.
| A．he believed silence was a source of strength |
| B．he thought it useless to defend obviously correct ideas |
| C．he believed in conflict rather than in unquestioning agreement |
| D．he knew the more he said ,the more people would resent him |
What would be the best title of the passage?
| A．Jefferson’s Great Works | B．Jefferson’s Philosophy |
| C．Jefferson’s Teaching | D．Jefferson's Life Story |
For a lang time,a boy wonder why his next-desk-pal was always the first in the class , whereas he could only rank the 21st.
At home,he asked his mom：“Am I more stupid than other kids? How can I alwasys fall behind? I just can’t come with an answer.”Mom was aware that her son’s selfrespect had been damaged by the ranking system,but she didn’t know what to say to help.
She tended to say that intelligence differs and that yes,her son’s friend really was the smarter boy.But that would so upset her son .Thank goodness she resisted the temption (诱惑)to say it .
Her son and his friend went on to high school that year,but despite trying as hard as he could,her son’s friend still outdid him.But she was proud of her boy for his hard work, sincerely proud,It was aroud this time that she decided to take him on a trip to the seaside,On the trip,she at last found an answer for him.
Today her son no longer care about rankings.He doesn’t have to,for he himself is now the top of the class at the national unversity he attands,After university his Teachers and peers fully expect him to have promising career.
Invited to speak to his old high school, he mentioned a valuable childhood experience. It concerned that holiday his mother had prepared for them: “Once, on a trip to the sea, my mother and I were lying on the beach. She pointed to the sea and said to me: Do you see the seabirds fighting for food out there? When a wave comes near, the little birds rise quickly. The clumsy(笨拙的)seagulls are far slower and have to struggle to get away from the wave. But these clumsy birds prove to have the biggest, strongest wings, which allow the bird to travel the furthest. When the season changes, they leave for foreign shores, leaving the little birds behind. Son, I have a feeling that you are one of those seagulls.”The story convey the message that.________.
| A．competion between students is good for society |
| B．only rankings show intelligence of a child |
| C．chilren take competion among them to heart |
| D．parents should build up chilren’s self-respect |
Form the 2nd paragraph,we can see that the mother
| A．decided to help with her son’s homework |
| B．saw the negative effects of the ranking system |
| C．knew her son was weak in his study |
| D．felt sorry for her son’s bad behavior |
We can infer from the passage that
| A．the mother was cafeful to protect her son’s self-respect |
| B．the mother was not strong enough to face the truth |
| C．the son knew intelligence didn’t mean anything |
| D．the son would forget his rankings soon after leaving high school |
Which of the following has the similar meaning with the underlined word “outdid”?
A.was equal to B..laughed at C did better than D.worked harder than